The present invention relates to a golf club head, more particularly to a face portion having a specific thickness distribution.
Recently, there have been widely used wood-type hollow golf club heads whose face portion is made of a thin metal material in order to increase the carry distance of the hit ball, while providing a thicker central region to provide the necessary strength and durability. In this face structure, since the central region is surrounded by the relatively thin region, there is a tendency that the boundary portion between the thick central region and the relatively thin surrounding region becomes a weak point at the time of off-center shots.
In order to solve this problem, it has been proposed in US-2003-144079-A1 that the thin surrounding region is provided with narrow ribs extending radially from the central thick region, wherein the narrow ribs are disposed around the central region at almost same angular intervals.
The narrow ribs can reinforce the thin surrounding region, and the strength and durability can be increased. But, the deflection of the face portion at the time of off-center shots is decreased and as a result, the carry distance of the hit ball is also decreased.